This day in History 1953- Soviets have H bomb too

Dissident Soviet physicist Andrei Sakharov, father of the Soviet H-bomb.
Physicist Andrei Sakharov, who would eventually become one of the USSR's most famous dissidents, was one of the chief designers of its hydrogen bomb. That weapon carried the explosive power of 400 kilotons of TNT, making it roughly 26 times more powerful than the atomic bomb dropped by the Americans on Hiroshima eight years earlier.
Thus began a long rivalry of bomb-test one-upmanship between the world's two superpowers, dragging on through the 1950s into the '60s.
The Soviets, especially, developed a fondness for the hydrogen bomb and tested increasingly powerful versions. The tests culminated in 1961 with the dropping of the so-called Tsar bomb, packing a 60-megaton wallop, making it the most powerful thermonuclear device ever detonated.